Questions, negations, passives, and
The sentence patterns surveyed so far have largely been "simple affirmative active declarative," which we will abbreviate as SAAD. An example of a SAAD sentence is Los líderes de Occidente se reunirán mañana en Bruselas. It is SIMPLE in not containing any internal clauses; there is only one verb with its associated NPs and Advls (sometimes grouped together as the verb's ARGUMENTS). It is AFFIRMATIVE as opposed to negative; and it is ACTIVE as opposed to the passive sentence Los líderes serán reunidos por el primer ministro. It is DECLARATIVE in asserting information, not asking a question or giving a command that overtly requires a hearer's response.
SAAD structure can be changed by transformations that rearrange, delete, and introduce elements. Though preserving the underlying relationships of the constituents as defined in deep structure by the PSRs, transformations edit their surface form and produce alternative patterns. We have already seen several processes that are treated as transformations, including nominalization (v. 8.4.1), agreement (v. 8.1.1, 11.2.1), clitic promotion (v. 9.4.1, 11.2.1), and "personal" a insertion and rules for preposing and postposing (v. 11.2–11.3.3). Similarly, questions, negations, passives, and commands have often been described as transformational variants (or TRANSFORMS) of the more basic SAAD types.1 Teachers should recognize that this treatment resembles the usual pedagogical approach whereby students first learn a structure such as Víctor admira a Mercedes and then learn ways to change this to ¿ Admira Víctor a Mercedes?, to Mercedes es admirada por Víctor, and so on.
English and Spanish have several kinds of questions and form them in similar ways—but with numerous differences of detail. The three most important question types are tag questions, yes/no questions, and information (Wh-) questions.